Recent answers to Firefox only opens googlehttps://support.mozilla.org/kn/questions/9706172013-09-08T09:13:28-07:00Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test 2013-09-08T09:13:28-07:00cor-elhttps://support.mozilla.org/kn/questions/970617#answer-477444

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.

Do a malware check with some malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.
All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

I did temporary disable the antivirus.
2013-09-08T07:20:10-07:00adexhttps://support.mozilla.org/kn/questions/970617#answer-477406

I did temporary disable the antivirus.

Have you tried safe mode, maybe a AV is interfering.
http://windows.microsoft.com/en-us/windows/st2013-09-08T06:46:19-07:00Waka_Flocka_Flamehttps://support.mozilla.org/kn/questions/970617#answer-477401

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state whil2013-09-07T17:22:18-07:00ComputerWhizhttps://support.mozilla.org/kn/questions/970617#answer-477251

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information.
Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

Go to Firefox &amp;gt; Help &amp;gt; Troubleshooting Information.

Click the "Reset Firefox" button.

Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.